You may need to do some assessment to see where this student is at mathematically. If he is truly advanced, and the parent is already working on meeting this need, he may need to be set up in an accelerated math program. Although Investigations has wonderful explorations into concepts, it CAN be a bit boring at times for students mathematically gifted. Yes, accommodations can be made, but it is difficult to always make these accommodations unless you have done it for years. As I teach the 5th grade units, I do not have the next grade concepts to pull into my teaching and am not yet strong enough in my use of the units to be able to expand out immediately as I see my strong students getting bored.
On a personal note... I am in need of accelerating my own son in math. I am considering blending traditional mathematics curriculum with Investigations at the grade he is working. I feel the geometry units are especially strong in Investigations compared with the traditional math curriculum. Perhaps this father would like to see the concepts that can be taught through Geo-logo.